Fire-alarm.



PATENTED JUNE 19, 1906.

G. H. OATWAY & C. E. MAY.

FIRE ALARM.

APPLICATION FILED APR. 3, 1905.

desirable.

"UNITE STAT-Es PATENT OFFICE.

GEORGE'HENRY OATWAY AND CHARLES EDWARD AY, OF LONDON,-

' ENGLAND.

Fins-ALAR Specification of Letters Patent.

Patented June 19, 1906.

Application filed April 3, 1906. Serial No. 253.555.

To all whom it may concern:

Be it known that we, GEORGE HENRY OAT- wer, managing director of The May-Oatwa'y Fire Appliances, Limited, and CHARLES ED- wum MAY, director of The May-atway Fire A diainces, Limited, subjects of the Kins 0 reat Britain, residing at 92 and 94 Paul street, in the city of London, En land, heve invented certain new and usefi improvements in Fire-Alarms, of which the following is e specification.

This invention relates to fire-alarms of the class in which an electric circuit is closed or opened or an alarm otherwise given. by the xpension and consequent slsckenin' of a wire. Alarms of this class are descri ed in the British specifications, No. 23,018 of 1900 and No. 5,984. of 1901.

in order to obtain certainty of working with such apparatus and to prevent false alarms caused by vibration, it is necessary for the expansion of the wire in case of fire to be suficient to considerably increase its length, and this has heretofore involved the use of a somewhat long wire, which is sometimes inconvenient.

The object of the present invention is to obtain the necessary slackening with a. much shorter wire. For this purpose the end of the wire instead of being fixed to the base as before is attached to the long srni of e lever, the shorter arm of which is pivoted to one end of s. metallic rod whose other end is fixed to the base, so that the expansion of the bar turns the lever about its pivot, and so slacks the wire, thus adding to the slackening caused by its own expansion. The wire msy he replaced by s cord or the like which does not expand with heat 3 but this is not usually in this specification such a cord or the like is included under the term wire.

Tlhe rod may be replaced by a. tube or even by s flexible wire ii the letter is always kept in tension by e. suilicicnt strain on the other wire. In this specification such a tube or wire is included under the term rod.

The hose upon whi h whol arrangement is carried usual, of 9. bar or pensetor by equally with the tempercture is .3: alarms.

Figure elevetion of an apparatus constructed according to this invention, and Fig. 2 is a similar view of its two ends to a larger scale. Fig. 3 is a. view similar to Fig. 1, but in addition showin one way in which the device may be emp oyed to close a signaling-circuit.

a is a plate forming the base of the appare tus and serving as the com ensator.

b is the wire. Its end Z) 1s fixed to one arm of a lever b, whose movement is limited by a stop I), the wire being kept at the proper tension by a weight If, hung from the other arm of the lever. The cfiiciency of the apparatus can be tested it any 'time by raising the weight b, and so slackening the wire. The end 5 of the wire is connected to the long arm of the lever c, pivoted at c to the plate a.

' to melt end let go when some predetermined temperature is reached.

When the temperature of the room rises gradually, the plate 0., the wire 1/, end the rod d all expand approximately equally, so that the droop of the wire 1) remains substantially constant, and until the temperature is reached at which the solder lets go no alarm is given. When, however, a fire takes place and the temperature of the room rises rapidly, the.

rod d and wire I) (if it be metallic) expand more quickly than the plate c.- The expansion of the rod (1 in this case turns the lever 0 about its pivot, thereby slackening the wire and increasing the slsckeninlg caused hv its own expansion, with the resu t that an alarm is given before the temperature rises suill' ciently to cause the solder to let 0.

In Fig. 3 a contiict-makin b0 X is shown connectcdwith the wire 17. his bob is ad opted to engage contact-fin crs Y Y, which are connected to wires j y or a signclingcircuit, which ncrmsli open at the contacts Y Y. When the wire b expands, the bob X drops into contact with the fingers Y Y and closes the c uit and gives the alarm.

ii h ole-1m 1s 1. The combinstion of c compensator or base constructed to expand a proximately equally with the other parts of t e apparatus when the rise of temperature is s ow and which is exposed to changes in the atmosphere, a lever ivoted to the base, a quicklyexpansible rod having one end fixed to the base and the other end pivotally connected with one arm of the lever and a flexible wire having one end connected to the base and the other end to' the other arm of the lever.

Z. The combination of a compensator or base constructed to expand approximately equally with the other parts of the a paratus When the rise of temperature is s ow and which is exposed to changes in the atmos phere, but to expand more slowly than the other parts when the rise of temperature is sudden, a lever pivoted to the base, an expansible rod havmg ,one end fixed to the base and the other end pivotally connected with one arm of the lever, and an expansible and flexible Wire having one end connected to the base and the other end to the other arm of the lever.

3. The combination of a compensator or base constructed to expand approximately equally with the other parts when the rise of tern eratu're is slow, but to expand more slowly than the other parts when the rise oftemperature is sudden, an expansible rodhaving one end fixed to the base and the other to one arm of the lever, a weighted lever pivoted to the base and a wire havin one end. connected to the weighted lever an, the other end to the other arm of the first lever. v

4.- The combination of a compensator or base constructed to expand approximately equally with the other parts of-the, apparatus when the rise of temperature is slow, but to expand more slowly than i the other parts when the rise of temperature is sud'den, an expansible rod-havin one end fixed to the base and the other en ivoted to one arm of the lever, a Weighted ever pivoted to the base and .an expansible Wire having one end connected to the lever and the other end to the other arm of the first lever.

GEORGE HENRY oArWAY. CHARLES EDWARD MAY. Witnesses: I

H. D. JAMEBON, vT. L. RAND. 

